Referring to FIG. 4, there is shown a prior art teat for a feeding bottle. When in use with a baby just born, it is necessary to pierce the nipple of the teat with a needle. However, as the baby grows up gradually, he (or she) will have a greater appetite and this will make him or her feel that it is difficult to suck the milk from the feeding bottle if the needle hole in the nipple of the teat is not enlarged. Hence, the nipple of the teat is required to be cut off to increase the flow rate. Nevertheless, it is very difficult to clip the nipple of the teat as desired so that the nipple is often clipped excessively or insufficiently. If the nipple is clipped excessively, the baby will be choked with the milk, and if the nipple is clipped insufficiently the baby will feel that it is difficult to suck the milk from the feeding bottle.
It is, therefore, an object of the present invention to provide a teat for a baby's feeding bottle which may obviate and mitigate the above-mentioned drawbacks.